Effect of combination treatment of protocatechuic acid with 5-fluorouracil and oxaliplatin on colon cancer Caco-2 cell line

Among the most common antitumor drugs used in the treatment of colon cancer are 5-fluorouracil and oxaliplatin (5-FU and OXA). However, both these drugs have many side effects, and hence there is a need for new treatment\approach to reduce the side effects aas well as drug concentration. In this context, here, we investigated the effect of addition of protocatechuic acid (PCA) onto either monotherapies or combination therapies of 5-FU and OXA on the human colon cancer (Caco-2) cell line. In addition, we did evaluate the synergistic effect of PCA with 5-FU and OXA. Further, we determined the suppressive effects of different doses of PCA alone or in combination with 5-FU/OXA on cell proliferation after 24 and 48 hours. We identified a suppressive effect of PCA on cell viability at 48 h starting from the dose of 50 µM Matrix metalloproteinase-2 (MMP-2) and MMP-9 gene expression levels and apoptotic effects showed significant increases and decreases depending on the dose and time applied in the experimental groups. The highest synergistic activity was seen at 2:1 concentration of 5-FU+ PCA. Our findings indicate the presence of the cytotoxic and apoptotic effects of PCA in Caco-2 cells at 48 h, increasing with a dose- and time-dependent manner.

LDHA inhibitor combined with targeted drugs synergistically inhibit the proliferation of fumarate hydratase-deficient renal cell carcinoma cells / 现代泌尿外科杂志

【Objective】 To explore the therapeutic effects of lactate dehydrogenase A (LDHA) inhibitor and targeted drugs on fumarate-hydratase-deficient renal cell carcinoma (FH-d RCC). 【Methods】 RNA-sequencing was used to detect the mRNA expression in FH-d RCC tissues, which was further validated with real-time fluorescence quantitative PCR and immunohistochemistry. Human-derived FH-d RCC cell line UOK262 and murine-derived FH-d RCC cell line FH1-/-CL19 (CL19) were treated with LDHA inhibitor [(R)-GNE-140] and listed kidney cancer targeted drugs (Axitinib, Cabozantinib, Sunitinib, Sorafenib, Pazopanib, Everolimus) respectively, and then treated with LHDA inhibitor in combination with the targeted drugs to observe the alteration of cell proliferation. The combination index (CI) of different dose groups of the combination drugs were analyzed with CompuSyn software to determine the optimal combination regimen. 【Results】 LDHA inhibitor and targeted drugs, including Cabozantinib, Sorafenib and Sunitinib, had a significant inhibitory effect on the proliferation of FH-d RCC cells, and the combination of Cabozantinib and Sorafenib or Pazopanib had a significant anti-tumor effect. 【Conclusion】 LDHA inhibitor combined with targeted drugs can significantly inhibit the growth of FH-d RCC cells, indicating that LDHA may be a potential therapeutic target of FH-d RCC.

A cyclodextrin-based nanoformulation achieves co-delivery of ginsenoside Rg3 and quercetin for chemo-immunotherapy in colorectal cancer

The immune checkpoint blockade therapy has profoundly revolutionized the field of cancer immunotherapy. However, despite great promise for a variety of cancers, the efficacy of immune checkpoint inhibitors is still low in colorectal cancer (CRC). This is mainly due to the immunosuppressive feature of the tumor microenvironment (TME). Emerging evidence reveals that certain chemotherapeutic drugs induce immunogenic cell death (ICD), demonstrating great potential for remodeling the immunosuppressive TME. In this study, the potential of ginsenoside Rg3 (Rg3) as an ICD inducer against CRC cells was confirmed using in vitro and in vivo experimental approaches. The ICD efficacy of Rg3 could be significantly enhanced by quercetin (QTN) that elicited reactive oxygen species (ROS). To ameliorate in vivo delivery barriers associated with chemotherapeutic drugs, a folate (FA)-targeted polyethylene glycol (PEG)-modified amphiphilic cyclodextrin nanoparticle (NP) was developed for co-encapsulation of Rg3 and QTN. The resultant nanoformulation (CD-PEG-FA.Rg3.QTN) significantly prolonged blood circulation and enhanced tumor targeting in an orthotopic CRC mouse model, resulting in the conversion of immunosuppressive TME. Furthermore, the CD-PEG-FA.Rg3.QTN achieved significantly longer survival of animals in combination with Anti-PD-L1. The study provides a promising strategy for the treatment of CRC.

Quantitative analysis of effects of salvianic acid a combined with hydroxy safflower yellow a on rat endothelial cells after hypoxic injury using the combination index method

Abstract Cerebrovascular disease is the second most serious disease in the world. It has the features of high morbidity, high mortality and recurrence rate. Numerous research on the compatibility of Chinese medicine with effective ingredients of cerebral ischemia has been made during the past decades. The purpose of this study is to quantitatively analyze the combined pharmacological effect of effective ingredients in Danshen and Honghua (Dan Hong) on rat microvascular endothelial cells after gradually oxygen-glucose deprivation. The experimental concentration range for the compatibility of two effective ingredients were determined in the preliminary experiments by Cell Counting kit-8 (CCK-8) method. Drugs were added to rat brain microvascular endothelial cells at a non-toxic dose level. After that, the cells were cultured for 12 h, and placed in a hypoxic environment. Finally, the cell survival rate was used as a measure of drug effect. In order to determine synergism or antagonism, the combination index (CI)-isobologram method was performed to analyze the data from the experiments. Based on this theory, the potencies of each drug and the shapes of their does-effect curves are both taken into account. The results show that the synergism or the antagonism between two effective ingredients compatibility change with different proportion and dosage. Furthermore, it can be seen from the results of these experiments that when these drugs are used in combination, the dosage required to achieve the same therapeutic effects is greatly reduced compared with the case of single one. It is worth mentioning that our experiments also prove that the median-effect equation and the CI method can be applied in the field of traditional Chinese medicine.

Combination effect of doxorubicin and HIF inhibitor on MCF-7 CD44+/CD24- subpopulation cells in hypoxic condition

Abstract Hypoxia-inducible factors (HIFs) and cancer stem cells (CSCs) are two challenging causes of radiotherapy and chemotherapy resistance, leading to most cases of failure and recurrence in breast cancer therapy. This study was conducted to investigated the inhibitory effect of combination therapy with doxorubicin (an anthracycline) and FM19G11 (an HIF inhibitor) on MCF-7 cells and their CSC-like cells (CSC-LCs). MCF-7 CSC-LCs with a CD44+/CD24- phenotype were sorted and characterized by flow cytometry. A combination of doxorubicin and FM19G11 caused more cytotoxic effects on MCF-7 and CSC-LCs compared to doxorubicin monotherapy. The largest synergistic effect was observed in CSC-LCs under hypoxic conditions; however, MCF-7 cells showed no synergism in normoxic conditions. The administration of doxorubicin and FM19G11 induced late apoptotic and necrotic cell death in MCF-7 and CSC-LCs. Additionally, G2 phase arrest was observed in both cells. Our results demonstrated that co-administration of FM19G11 and doxorubicin had a synergistic effect in hypoxia and improved drug resistance in breast cancer stem cells.

Cancer-specific calcium nanoregulator suppressing the generation and circulation of circulating tumor cell clusters for enhanced anti-metastasis combinational chemotherapy

Tumor metastasis is responsible for chemotherapeutic failure and cancer-related death. Moreover, circulating tumor cell (CTC) clusters play a pivotal role in tumor metastasis. Herein, we develop cancer-specific calcium nanoregulators to suppress the generation and circulation of CTC clusters by cancer membrane-coated digoxin (DIG) and doxorubicin (DOX) co-encapsulated PLGA nanoparticles (CPDDs). CPDDs could precisely target the homologous primary tumor cells and CTC clusters in blood and lymphatic circulation. Intriguingly, CPDDs induce the accumulation of intracellular Ca

Astemizole, an inhibitor of ether-à-go-go-1 potassium channel, increases the activity of the tyrosine kinase inhibitor gefitinib in breast cancer cells

Abstract Background Expression and activity of the potassium channel ether-à-go-go-1 (EAG1) are strongly related to carcinogenesis and tumor progression, which can be exploited for therapeutic purposes. EAG1 activity may be reduced by preventing its phosphorylation with epidermal growth factor receptor (EGFR) kinase inhibitors and by astemizole, which blocks the channel pore and downregulates its gene expression. Objective We aimed to study the potential cooperative antiproliferative effect of the EGFR inhibitor gefitinib and the EAG1-blocker astemizole, in breast cancer cells. Materials and Methods The cells were characterized by immunocytochemistry. Inhibitory concentrations were determined by non-linear regression analysis using dose-response curves. The nature of the pharmacological effect was evaluated by the combination index equation while cell cycle analysis was studied by flow cytometry. Results Astemizole and gefitinib inhibited cell proliferation in a concentration-dependent manner, with inhibitory concentrations (IC 50) values of 1.72 µM and 0.51 µM, respectively. All combinations resulted in a synergistic antiproliferative effect. The combination of astemizole and gefitinib diminished the percentage of cells in G2/M and S phases, while increased accumulation in G0/G1 of the cell cycle. Conclusions Astemizole and gefitinib synergistically inhibited proliferation in breast cancer cells expressing both EGFR and EAG1. Our results suggest that the combined treatment increased cell death by targeting the oncogenic activity of EAG1.

Synergistic antioxidant interactions between green tea and Ocimum gratissimum

Objective: To evaluate the antioxidant interactions between aqueous infusions of green tea and Ocimum gratissimum at different ratios. Methods: Antioxidant activities of aqueous infusion of green tea and Ocimum gratissimum (leaves) alone or in combination at various proportions (3:1, 2:1, 1:1, 1:2, 1:3) were determined by DPPH, ABTS, NO and ex-vivo assays including lipid peroxidation and haemolysis. Total phenolic content and flavonoid content was calculated by Folin-Ciocalteu reagent and aluminum chloride colorimetry method, respectively. A correlation study was also conducted between the antioxidant activity and total phenolic/flavonoid content of various infusions. The interactions were analyzed by combination index applying CompuSyn software. Results: Green tea exhibited high radical scavenging ability as compared to Ocimum gratissimum infusion. Combination of green tea and Ocimum gratissimum exhibited moderate antagonism to strong synergistic interaction at various ratios. A strong correlation was found between total phenolic content/total flavonoid content and antioxidant activities of individual infusions (green tea and Ocimum gratissimum). For binary mixture at different ratios, a weak to strong correlation was observed between total phenolic content and antioxidant activity and almost no correlation between total flavonoid content and antioxidant potential. Conclusions: Overall, green tea and Ocimum gratissimum combination (1:1) displayed the highest antioxidant potential and maximum synergism.

Synergistic antioxidant interactions between green tea and Ocimum gratissimum

Objective: To evaluate the antioxidant interactions between aqueous infusions of green tea and Ocimum gratissimum at different ratios. Methods: Antioxidant activities of aqueous infusion of green tea and Ocimum gratissimum (leaves) alone or in combination at various proportions (3:1, 2:1, 1:1, 1:2, 1:3) were determined by DPPH, ABTS, NO and ex-vivo assays including lipid peroxidation and haemolysis. Total phenolic content and flavonoid content was calculated by Folin-Ciocalteu reagent and aluminum chloride colorimetry method, respectively. A correlation study was also conducted between the antioxidant activity and total phenolic/flavonoid content of various infusions. The interactions were analyzed by combination index applying CompuSyn software. Results: Green tea exhibited high radical scavenging ability as compared to Ocimum gratissimum infusion. Combination of green tea and Ocimum gratissimum exhibited moderate antagonism to strong synergistic interaction at various ratios. A strong correlation was found between total phenolic content/total flavonoid content and antioxidant activities of individual infusions (green tea and Ocimum gratissimum). For binary mixture at different ratios, a weak to strong correlation was observed between total phenolic content and antioxidant activity and almost no correlation between total flavonoid content and antioxidant potential. Conclusions: Overall, green tea and Ocimum gratissimum combination (1:1) displayed the highest antioxidant potential and maximum synergism.

Susceptibility of boll weevil to ready-to-use insecticide mixtures / Suscetibilidade do bicudo-do-algodoeiro a misturas de inseticidas prontas para uso

Boll weevil is the major cotton pest in Brazil, and insecticides are widely recommended against it. We determined the susceptibility of boll weevil to insecticides either in single or in mixture ready-to-use formulations, which are registered to spray cotton fields under the hypothesis that mixtures are more toxic to the target pest. Concentration-mortality curves were determined to adult species, simultaneously through dried residues and ingestion. Ten insecticide formulations were studied with five in mixture (lambda-cyhalothrin + thiamethoxam, lambda-cyhalothrin + chlorantraniliprole, thiamethoxam + chlorantraniliprole, and fenitrothion + esfenvalerate) and their five respective single formulations. Cotton leaf discs and cotyledons were dipped into insecticide dilutions prepared by diluting the commercial products into distilled water. Adult mortality was assessed 48 hours after caging adults on treated and untreated materials. The LC50s-concentrations varied from 0.004 to 0.114 g a.i./L, with a relative potency between single and mixture ones, varying from 1.37- to 29.59-fold. Furthermore, lambda-cyhalothrin and thiamethoxam in single formulation were the most toxic insecticides to boll weevil. Among insecticide mixtures, only lambda-cyhalothrin + chlorantraniliprole resulted in a synergic effect; whereas the remaining mixtures showed an antagonistic effect. Therefore, except for the mixture of lambda-cyhalothrin + chlorantraniliprole, the remaining mixtures did not enhance toxicity against the boll weevil and should be recommended only when aimed at different purposes.(AU)

Bicudo-do-algodoeiro é a principal praga do algodoeiro no Brasil, sendo o uso de inseticidas amplamente recomendado para o seu controle. A suscetibilidade do bicudo-do-algodoeiro foi determinada a inseticidas em formulação simples ou em misturas prontas para uso, as quais têm sido recomendadas para pulverizar campos de algodão sob a hipótese de serem mais tóxicas à praga alvo. Assim, curvas de concentração-mortalidade foram determinadas para adultos do bicudo contaminados, simultaneamente, via resíduo seco e ingestão dos inseticidas. Dez formulações foram estudadas, sendo cinco misturas (lambda-cialotrina + tiametoxam, lambda-cialotrina + clorantraniliprole, tiametoxam + clorantraniliprole e fenitrotiona + esfenvalerato) e suas respectivas cinco formulações simples. Folhas e cotilédones do algodoeiro foram mergulhados em diluições do inseticida preparadas com os produtos comerciais e água destilada. A mortalidade adulta foi avaliada 48 horas após o acondicionamento dos adultos em materiais tratados e não tratados. As concentrações de CL50s variaram de 0,004 a 0,114 g i.a./L, com potência relativa entre formulação simples e misturas, variando de 1,37 a 29,59 vezes. A lambda-cialotrina e o tiametoxam em formulações simples foram os inseticidas mais tóxicos para o bicudo. Entre as misturas, aquela preparada com lambda - cialotrina + clorantraniliprole resultou em um efeito sinérgico, enquanto as demais misturas mostraram um efeito antagonista. Portanto, exceto pela mistura de lambda-cialotrina + clorantraniliprole, as demais misturas não demonstraram maior toxicidade para o bicudo-do-algodoeiro e devem ser recomendadas somente quando objetivam finalidades diferentes.(AU)

Effect of Topotecan in Combication with Other Antitumor Drugs in Vitro / 대한부인종양콜포스코피학회잡지

OBJECTIVES: The aims of this study were to evaluate the interaction of topotecan with adriamycin, etoposide, 5 fluorouracil (5 FU) and mitomycin C in the established four ovarian cancer cell lines and three cervical cancer cell lines and to establish whether the combination of topotecan with other antitumor drugs would be a synergism for chemotherapy in patients with ovarian and cervical cancer, METHODS: Five antitumor drugs were tested for synergism and antagonism in combination studies in four ovarian cancer cell lines (A2780, A2780 cisplatin resistant variant, A2780 taxol resistant variant, SKOV3) and three cervical cancer cell lines (HeLa, SiHa, ME180). Cytotoxic effects were determined by MTT assay. Synergic interaction was calculated by the median effect principle in which combination index (CI) of less than one suggest a synergic interaction. RESULTS: Dm value of topotecan against SKOV3 (2.07 ug/ml), HeLa (3.32 ug/ml), SiHa cell lines (2.5 ug/ml) were above peak plasma concentration of topotecan (0.5 ug/ml) but most antitumor drugs tested in combinations index were within clinically relevant range. Combination with topotecan showed a synergic effect (CI<1) in seven cancer cell lines at a intermediate or high level of cytotoxicity especially with mitomycin C (6/7), etoposide (6/7), 5 FU (6/7) and adriamycin (4/7). Most striking findings were that a synergic effect was shown in all ovarian cancer cell lines to topotecan/mitomycin C, topotecan/5 FU and topotecan/esoposide combination showed a synergic effect in all cervical cancer cell lines. Topotecan/adriamycin combination showed synergism at an intermediate or high level of cytotoxicity in cisplatin or Taxol resistant ovarian cancer cell lines (A2780CP, A2780TX, SKOV3). CONCLUSION: These results suggested that topotecan showed a synergic effect with a wide range of antitumor drugs: adriamycin, etoposide, 5 FU, mitomycin C in ovarian and cervical cancer cell lines. Combinations of topotecan/mitomycin C, topotecan/5 FU and topotecan/adriamycin for ovarian cancer and a combination of topotecan/etoposide for cervical cancer seemed worthy of consideration for clinical application.